EP3559323A1

EP3559323A1 - Method for producing fibres and nonwoven fabrics by solution blow spinning and nonwoven fabric produced thereby

Info

Publication number: EP3559323A1
Application number: EP17835818.0A
Authority: EP
Inventors: Arun Prasad Venugopal; Andreas Tulke; Georgios Toskas
Original assignee: Groz Beckert KG
Current assignee: Groz Beckert KG
Priority date: 2016-12-21
Filing date: 2017-12-15
Publication date: 2019-10-30
Also published as: US20200095706A1; CN110325674A; KR20190092568A; WO2018114645A1; DE102016125182A1; CA3048069A1; JP2020502383A

Abstract

The invention relates to the use of a parent solution (A) in the method for producing fibres for a nonwoven fabric by means of solution blow spinning. Water is used as the solvent for the parent solution (A). At least one water-soluble polymer and preferably precisely one water-soluble polymer is dissolved in the water of the parent solution (A). The parent solution (A) also includes at least one surfactant and optionally a plasticizer for the at least one polymer used. Using this parent solution (A) it is possible to produce fibres (24) by solution blow spinning.

Description

Process for producing fibers and nonwovens by solution blow spinning and nonwoven fabric made therewith

[0001] The invention relates to the use of an off ^¬ temporary solution for the production of fibers, in particular fibers micro- or Submikrofasern or nanofibers by Solution-blow spinning, and such a spinning process for the production of fibers and a nonwoven fabric produced by the method. Solution-Blow-Blowing is a spinning process in which a source solution emerges from at least one exit nozzle and is transported to a collector under the action of a process gas to form solid fibers consequently synthetic fibers.

For the production of fibers, there are various

Method. For example, methods are known in which fibers are produced by extruding a liquid or viscous mass through openings. Such methods are referred to as melting, wet or dry spinning process, depending on how the mass in question has been asked ^¬ forth or liquefied.

If particularly fine fibers, that is fibers are to be produced with a small fiber diameter, the centrifugal spinning process and the electrostatic spinning, or the solution-blow-blowing are particularly suitable. Such fibers are needed especially for the production of filters. In the previous method has the disadvantage that usually polluting and / or the health of the workforce straining ^{Lösungsmit ¬} tel are used to produce the fibers. Such solvents are often expensive too. Therefore, water is increasingly in ^¬ before-mentioned method for environmental and cost reasons, as the solvent (i.e., the use of solutions of water soluble polymers wässri- gen) is provided. Water is environmentally friendly, non-toxic and very inexpensive compared to other solvents.

The use of water as a solvent for spinning processes is already known. For example, JP 2010-150712 A discloses a process for producing fibers by electrostatic spinning which uses aqueous solutions of water-soluble polymers.

The electrostatic spinning has a Prinzipbe ^¬ dingt comparatively low productivity. As a result, fiber production by electrostatic spinning is very expensive. The electrostatic spinning can therefore be host ^¬ cally used only for the production of fibers, which are used in very high-priced products.

US 8 641 960 Bl describes a solution-blow spinning in which solutions of the polymers in question are converted by means of a process gas stream into solid fibers for the production of very fine polymer fibers. Such a solution blow-spinning is opposite the electrostatic spinning of advantage because it enables a hundred to tau ^¬ send fold higher productivity. However, it has not yet been possible to produce fibers with a sufficient or high quality from environmentally friendly aqueous solutions by solution blow spinning. It can be regarded as an object of the present invention to produce fibers and in particular high quality Fa ^¬ fibers environmentally friendly and efficient.

This object is achieved by the use of a starting solution during solution blow spinning with the features of claim 1 and a method with the Merkma ^¬ len of claim 16.

According to the invention, a starting solution is used to prepare the fibers by means of solution-blow spinning, is used in the water as a solvent. ^¬ to minimum the proportion of water is ^¬ range from 30% to 99% as solvent Be, preferably 50% to 95%, more preferably 60% to 90%. In the solvent is Wenig ^¬ one, and preferably a water soluble polymer dissolved exactly least. In addition, the starting solution contains at least one surfactant. The surfactant is a surfactant, which may also be referred to as a surfactant.

[0010] It has been found that through the application of the starting solution Ver ^¬ described a manufacture of good quality and / or high quality fibers can be achieved with a substantially constant fiber diameter. The fibers can be produced as microfibers, submicrofibers or nanofibers, ie with a fiber diameter in the micrometer range or sub-micrometre range or nanometer range by solution blow spinning. The order in which the substances added to the solvent are dissolved is not of considerable importance. The decisive factor is the composition of the output ^¬ solution. In solution-blow spinning, one or more jets of liquid are generated without atomizing the liquid into a spray. The liquid jets exit through a nozzle and are stretched by means of a Pro ^¬ zessgases, in particular compressed air. This fibers are formed. The liquid jets are preferably aligned substantially parallel to each other.

[0012] The fibers preferably have a ratio of length to an average thickness of at least 100: 1, preferably at least 500: 1, preferably Minim ^¬ least 1000: 1 and more preferably at least 10000: 1. Preferably, the fibers have a length of at least ei ^¬ nem millimeters, preferably of at least three Millime ^¬ tern, and more preferably of at least 5 millimeters.

It is advantageous if only water is used as solvent in the starting solution. The at least one water-soluble polymer or the at least one surfactant are not considered as solvents.

[0014] It is advantageous if the initial solution has finally ^¬ from water-soluble polymers. Other water-insoluble polymers are not included in the starting solution. At least one of the water-soluble polymers contained in the starting solution may be polyvinyl alcohol and / or polyvinyl methyl ether and / or polyethylene oxide and / or polyvinylpyrrolidone and / or polyethylene glycol and / or polyacrylic acid and / or polyacrylamide.

It is advantageous if the concentration of water in the starting solution in the range of 30 wt% to 99 wt%, preferably from 50 wt% to 95 wt%, more preferably from 60 wt% to 90 wt%.

The at least one water-soluble polymer can be selected from known polymers or polymer groups. The following list shows not complete ^¬ de Auzählung usable wasserlösicher polymers:

Cellulose derivatives such as methylcellulose, sodium carboxymethylcellulose, hydroxymethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose;

- natural gums such as gelatine, metal alginates (Na, K, Ca, Zn, Al), agar;

Starch derivatives such as hydroxyethyl starch ether, hydroxypropyl starch;

Dextran, hydroxyalkyldextran, carboxyl lower alkyldextran;

Water-soluble polysaccharides such as xanthan, pullulan, ulvan;

Polyamino acids with a free carboxyl group, such as aspartic acid and glutamic acid;

- Polyalkylenglykol such as polyethylene and polypropylene glycol;

- Synthetic derivatives such as polyethylene oxide, polyvinyl alcohol, polyvinyl methyl ether, polyvinylpyrrolidone, polyallyl, and diallylamines, Polydimethylaminoethylme- thakrylate, polyacrylic acid, Polystyrensulfonate, poly ^¬ acrylamides, neutralized Carbopol rubber and copoly- mers and mixtures of the geannten polymers.

In the starting solution, exactly one or NEN more of the above polymers may be included.

It is also possible to use copolymers or mixtures of the abovementioned polymers.

[0019] In the starting solution also may contain a plasticizer for the presence of at least one polymer, such as polyethylene glycol, propylene glycol, Glyze ^¬ rin, trimethylolpropane, di- / or tripropylene glycol with the ^¬ sen related compounds. In determining the concentration in the starting solution, the soft Some are attributed to the proportion of polymer and not the solvent ^¬ portion or the surfactant.

[0020] The concentration of the at least one wasserlös ^¬ union polymer of the starting solution is preferably in the range of 1 wt .-% to 70 wt .-%, preferably in the range of 5 wt .-% to 50 wt .-%, and more preferably in the Be ^¬ rich from 10 wt .-% to 40 wt .-% including an optional plasticizer. The specified Kon ^¬ concentration applies both when only a water-soluble polymer in the starting solution is present, as well as for starting solutions with more water soluble polymers.

In a preferred embodiment, the starting solution has exactly one water-soluble polymer which is suitable for a polymer used for the polymer

Plasticizers can be added.

[0022] It is further preferred if the concentration of the at least one surfactant in the starting solution is in the range from 0.001% by weight to 50% by weight, and more Preferably in the range of 0.01 wt .-% to 5 wt .-%, and more preferably in the range of 0.1 wt .-% to

1.5 wt .-% is. It is preferred if exactly one surfactant is contained in the starting solution.

[0023] It is advantageous if a surfactant is used which evaporates during the Solution-blow spinning in Wesentli ^¬ chen or completely. Thus, little or no residual amounts of the surfactant remain in the manufactured Fa ^¬ fibers. This prevents that the remains of Ten ^¬ sids leads to a negative impact on the mechanical properties and / or the chemical resistance of the fibers produced. In addition, surfactant residues may be detrimental to medical applications.

For the starting solution A, e.g. any surfactant mentioned in the table below may be used. In each case the commercial name of the surfactant and details of its composition are listed in the table.

lung

Berol Various predominantly ethoxylated compounds

Biodac ethoxylated C10 alcohol

Brij Ethoxylated fatty alcohols

Britex ethoxylated fatty alcohols

Calgene Various surfactants based on esters

Chemal Ethoxylated fatty alcohols

Chemax Various ethoxylated compounds

Alkanolamides and various ethoxylated Verbin¬

Chimi potions

Cithrol A, ML, MO and

MS Ethoxylated fatty alcohols

Cithrol, others glycol and glyceroleter

Crodamine amine oxides

Crodet ethoxylated fatty acids

Dehydol Ethoxylated fatty alcohols

Dehydrophene Ethoxylated alkylphenols

Ethoxylated fatty alcohols, for example, e.g. with blocked

Dehypon ends

Dobanol Ethoxylated fatty alcohols

Dowfax diphenyloxide-based sulfonates

Elfan Miscellaneous Sulfates and sulfonates

Emal sulfates of alcohols and ethoxylated alcohols

Emcol Various ingredients

Sulfates of alcohols and ethoxylated alcohols,

Empicol alkyl ether carboxylate

Alkanolamides and various ethoxylated Verbin¬

Employment

Empim sulfates and sulfosuccinates

Emulan Various ethoxylated compounds

Emulsified ethoxylated C16-C18 alcohols

Emulson Various ingredients

Ethylane Mostly ethoxylated compounds

Eumulgin Various ethoxylated compounds

Find Different Ethoxylated Compounds

Fluorad fluorocarbon-based surfactants

Genapol Ethoxylated fatty alcohols Geropon predominantly sulfosuccinates and taurates

Glucopone sugar-based surfactants

Hamposyl N-acyl sarcosinates

Hostapur alpha-olefinsulfonates and petroleum sulfonates

Iconol Various ethoxylated compounds

Igepal Various ethoxylated compounds

Imbentin ethoxylated alkylphenols

Lialet Ethoxylated fatty alcohols

Lipolan alpha olefinsulfonates

Lorodac Ethoxylated fatty alcohols

Lutensol Various ethoxylated compounds

Mackam Amphoteric

Macol Various ethoxylated compounds

Manro sulfates, sulfonates and alkanolamides

Marlipal Ethoxylated fatty alcohols

Marlophen NP Ethoxylated nonylphenol

Miranol imidazoline

Mirataine Betaine

Monamid alkanolamides

Montane sorbitan derivatives

Myverol monoglycerides

Neodol Ethoxylated fatty alcohols

Newcol Various ingredients

Nikkol Various ingredients

Ninol alkanolamides

Nissan Nonion Various ethoxylated compounds

Trydet Ethoxylated fatty acids and esters

Trylon Ethoxylated fatty alcohols and Ole

Tween ethoxylated sorbitan esters

Alkylbenzenesulfonates and sulfates of fatty alcohols and

Ufarol ethoxylated fatty alcohols

Ufaryl alkyl benzene sulfonates

Ufasan alkyl benzene sulphonates

Ungerol sulfates of ethoxylated fatty alcohols

Varamide alkanolamides

Variquate Quaternary ammonium surfactants

Volpo Ethoxylated fatty alcohols Witcamide alkanolamides

Witconate alkylarylsulfonates

Witconol glycol and glycerol esters

Ninol alkanolamides

Nissan Nonion Various ethoxylated compounds

[0025] The starting solution may contain in a Ausführungsbei ^¬ play solid particles, for example organic ^¬-specific and / or inorganic solid particles, such as S 1O2 T 1O2, Z Ru2, CuO, ZnO or Ag, preferably with particle ^¬ diameters smaller than the average Fiber diameter are.

Preferably, in addition to the solvent, to the at least one polymer, to the surfactant, to an optionally present plasticizer and optionally present solid particles, the starting solution has no further constituents.

The solution solution is blown out during solution-blow spinning by at least one first outlet nozzle of a pre ^¬ direction. At the same time, a process gas is emitted through at least one second outlet nozzle. Each first outlet nozzle is associated with at least one second outlet nozzle. The effluent process gas exits with high Ge ^¬ speed. Thus, the emerging from the first exit opening from ^¬ starting solution is entrained and carried by the process gas.

Preferably, the process gas is supplied under a pressure of 0.1 to 1000 psi, preferably from 5 to 80 psi and more preferably 10 to 60 psi of the at least two ^¬ th output nozzle. As a process gas can be used in one embodiment, air or compressed air. The air may be from the at least one second ^¬ gangsdüse supplied under a pressure of 10 to 80 psi.

The starting solution may be supplied to the at least one first outlet nozzle via a pumping device. As a pumping device, a metering pump, such as a gear pump, progressive cavity pump, reciprocating pump, peristaltic pump, diaphragm pump or other positive displacement ^¬ pe can be used.

Each first exit nozzle may be associated with exactly one second exit nozzle. In such exporting approximately ^¬ example, the second outlet nozzle, the first off ^¬ enclose gangsdüse partially or completely, preferably ^¬ annular manner. In another embodiment, each first outlet nozzle associated with at least two second gear from ^¬ nozzle. The second exit nozzles may be evenly distributed around the circumference of the first exit nozzles. Linear arrangements of the outlet nozzles can also be used.

[0032] The discharge direction, a first outlet nozzle is defined by the least and the outlet ^¬ direction, the associated through a second output nozzle is defined at least can be ori entiert parallel ^¬. Alternatively, it is also possible that the outlet direction of the at least one second outlet nozzle is inclined with respect to the outlet direction of the associated at least one first outlet nozzle.

[0033] The emerging process gas forms at least at a distance of a few millimeters, for example from 0 to 100 mm or 0.5 to 20 mm or 1 to 5 mm, a liquid jet of the starting solution. This liquid jet is carried or transported by the process gas. During this transport, the output ^¬ solution towards a collector to, preferably the solvent-containing and / or ent ^¬ holding surfactant substantially completely vaporized, for example at least 85% or at least 90% or at least 95% or at least 99 %. As a result, the polymer contained in the starting solution solidifies, which is then no longer dissolved in the solvent. The resulting fes ^¬ th fibers are collected on the collector.

[0034] The die-to-collector distance of an exit nozzle to the collector is at least preferably at least 20 centimeters, and more preferably at least 25 centi ^¬ meter. In one embodiment, the nozzle-collector distance may be about 30 to 70 centimeters. Before ^¬ preferably the nozzle-to-collector distance is smaller than 200 cm, and further preferably alive less than 100 centime ^¬ ter.

It is preferred that the boiling point of the Lö ^¬ sungsmittels and / or the surfactant is so small that the solvent and / or the surfactant evaporates after emerging from the at least one first Ausgangsdüse.

The process gas may have a focusing and / or bundling effect on the exiting solution. The formation of a liquid jet emerging from ^¬ temporary solution, by selection of process parameters such as the composition of the starting solution and / or the temperature of the starting solution and / or the temperature of the process gas and / or the ambient temperature ^¬ structure and / or the temperature of the output nozzle arrangement and / or the velocity of the process gas and / or the chemical composition of the process gas used and / or a suction capacity of a At the collector arranged suction device can be influenced.

[0037] The fiber diameter of the fibers produced is typically one-twentieth to one-thousandth of the opening diameter of at least a first from ^¬ opening. The fiber diameter is smaller than the diameter of the emerging from the at least one first outlet opening ^¬ liquid jet. By process parameters such as the speed of the emerging from ^¬ process gas, a reduction of the fiber diameter compared with the diameter of the emerging liquid jet can be obtained and set. If, for example, the exit velocity of the process gas is increased, the liquid jet is stretched as it were along its path, which reduces its diameter. In addition, the solvent and / or the surfactant is evaporated, so that the volume of liquid also decreases after it leaves the at least one first outlet nozzle.

[0038] The Solution-blow spinning, it is possible example ^¬ example, the produce a first output nozzle of, for example 0.2 to 1 mm, the fibers in the micron or submicron or nanometer range with diameters at least. In one embodiment, HERGÉ ^¬ presented fibers have an average diameter of about 50 Na nometern to 3 micrometers. The process gas may in one embodiment with egg ^¬ ner temperature of 0 ° C to 100 ° C, preferably 10 ° C to 90 ° C and more preferably 20 ° C to 80 ° C to the least ^¬ least a second exit nozzle ( 21) are supplied.

After the fibers have been produced, it may be advantageous if the fibers are aftertreated, for example by irradiation with high-energy radiation, such as UV light and / or heat treatment and / or plasma / corona treatment and / or a chemical treatment and / or other cross-linking treatments. By such a post-treatment, it is possible to obtain non-water-soluble fibers. Such treatment can be easily and inexpensively Runaway ^¬ leads.

[0041] All ranges given in the description ( "from ... to ...") are inclusive of being passed ^¬ range limit to understand, as long as no other is specified.

Advantageous embodiments of the invention will become apparent from the dependent claims, the description and the drawings. Hereinafter, preferred embodiments of the invention will be explained in detail with reference to the accompanying drawings. Show it:

1 shows a schematic, block diagram-like representation of an apparatus for producing fibers by means of solution-blow spinning,

FIGS. 2 and 3 each show a schematic principle. Zip representation of different output nozzle arrangements, each having a first output nozzle and at least one associated second output nozzle in plan view of the output nozzles,

FIGS. 4 and 5 show a schematic principle ^{illustration of} different linear outlet nozzle ^arrangements of a plurality of first and second outlet nozzles in plan view of the outlet nozzles,

[0046] Figures 6 and 7 are each a schematic cross-sectional view ^¬ an embodiment of an output ^¬ nozzle assembly each having at least a first Ausgangdüse and at least one associated second outlet nozzle, and

8 is a highly schematic representation of an embodiment of a manufactured fiber.

FIG. 1 shows a device 10 for carrying out a solution-blow-spinning process. The device 10 has a reservoir 11 for providing a starting solution A. The starting solution A is conveyed by means of a pumping device 12 to a solvent fluid port 13 of a spinneret device 14.

In addition, the spinneret device 14 has a process gas connection 15, by means of which the Spinndüsenein ^¬ direction 14 a pressurized process gas G is supplied ^¬ leads. The process gas G can be formed for example by air or compressed air. It can be taken from a pressure accumulator 16. Alternatively, instead of the pressure accumulator 16, a compressor or the like may be present be to suck in air from the environment and provide compressed air as process gas G. The process gas G may also be another gas such as nitrogen, helium or hydrogen.

[0050] The spinning nozzle assembly 14 has at least one first outlet nozzle 20. Each first Ausgangdüse 20 is we ^¬ nigstens associated with a second outlet nozzle 21st If meh ^¬ eral first output nozzles 20 are present, these differently oriented outlet or emission directions can have, which is shown schematically in FIG. 1

The at least one first exit nozzle 20 is fluidically connected to the solvent fluid port 13. The at least one second outlet nozzle 21 is fluidically connected to the process gas connection 15. Thus, the output solution A passes through the at least one first outlet nozzle 20 and the process gas G through the at least one second outlet nozzle 21.

[0052] The same time the initial solution A austre ^¬ tend process gas G increases with the starting solution A and för ^¬ this changed from the spinning nozzle device 14 in a direction away into a collector 22. Due to the high velocity of the process gas G 20, one or more liquid ^¬ keitsstrahlen 23 of the starting solution A. evaporated During the further path to the collector 22 through a contained in the Ausgangslö ^¬ solution A solvent formed above the mouth of the respective first Ausgangdüse and optionally further liquid components of the starting solution A, so that form solid fibers 24, which are collected at the collector 22. [0053] The collector 22 may have movable components on ^¬, such as a moving conveyor belt which is moved on drive rollers 25th In a modification to the illustrated embodiment, the collector 22 may be immovable, static executed.

Preferably, the collector 22 is gas-permeable and may be formed, for example, by a mesh or mesh-shaped carrier, such as a fine-meshed net. On the spinneret 14 opposite side of the collector 22, a suction device 26 may be present. The suction means 26 may be adapted to move the fibers 24 forming between the spinneret 14 and the collector 22 by suction of an air flow towards the collector 22.

[0055] The die-to-collector distance z between the nigstens we ^¬ a first outlet nozzle 20 and the collector 22 and / or between the at least one second outlet nozzle 21 and the collector 22 is 20 centimeters or 25 centimeters. In the illustrated embodiment can be ^¬ wear of the nozzle-to-collector distance for about 30 to 70 centimeters. Preferably, the nozzle-collector distance z is less than 200 centimeters and more preferably less than 100 centimeters.

[0056] In Figures 2 to 7 schematically illustrates exemplary different configurations each from ^¬ gear nozzle assembly 30 of the spinning nozzle device 14 are illustrated. The spinnerette assembly 14 may include one or more of the illustrated exit nozzle assemblies 30. These can be parallel or inclined to each other the spinning nozzle device 14 may be arranged or aligned. Each output nozzle device 30 has at least one and, for example, exactly one first output nozzle 20 for the starting solution A and at least one associated second output nozzle 21 for the process gas G.

[0057] In the example illustrated in Figure 2 embodiment 30, the output nozzle assembly exactly one ers ^¬ te outlet nozzle 20 and exactly one associated second off ^¬ gangsdüse 21. The first outlet nozzle 20 is arranged in the center of an annularly closed second outlet nozzle 21 which, in the exemplary embodiment, completely coaxially surrounds the first outlet nozzle 20.

By way of example, in the embodiment illustrated in Figure 3, the exit nozzle group 30 has exactly one first exit nozzle 20 and a plurality of associated second exit nozzles 21, for example four second exit nozzles 21. The number of second exit nozzles 21 can vary, with at least two second outlet nozzles 21 are present. The second outlet nozzles 21 are preferably arranged uniformly distributed in the circumferential direction around the first outlet nozzle 20. The second exit nozzles can also be a curved one

Slit shape and the first output ^nozzle 20 in de ^¬ ren circumferential direction partially enclose.

In general, the cross-sectional shape of the outlet ^¬ nozzles 20, 21 are arbitrarily selected. Illustrative of each circular or annular cross-sections are ver ^¬ anschaulicht. Other polygonal or slot-shaped straight or curved cross-sectional contours can also be provided, in particular for the at least one second Exit nozzle 21 of each output nozzle group 30th

Figures 4 and 5 show only by way of example that the output nozzles 20, 21 can be arranged in a linear arrangement in one or more rows next to each other.

In FIGS. 6 and 7 it is illustrated that the central longitudinal axes of the outlet nozzles 20, 21 of an outlet nozzle group 30 shown in phantom can be oriented parallel to one another (FIG. 6) or, alternatively, they can be oriented inclined relative to one another (FIG. 7). In the schematic shown in Figure 7 embodiment, the output direction for the process gas G is the Wenig ^¬ least inclined a second outlet nozzle 21 opposite the exit ^¬ direction of the initial solution A, according to the example in such a way that the process gas G at a plurality of circumferential positions per ^¬ weils obliquely to the central longitudinal axis or the exit ^¬ direction of the first output nozzle 20 is aligned.

The mouth of the at least one first exit nozzle 20 is spaced from the mouth of the at least one associated second exit nozzle 21, and preferably downstream of the process gas stream. The distance may for example be 0.5 to 20 mm or 1 to 10 mm or 1 to 5 mm or 2 to 3 mm.

The orientations of the exit directions according to FIGS. 6 and 7 can be provided both for the outlet nozzle group 30 from FIG. 2 and for the outlet nozzle group 30 from FIG. 3. To form the starting solution A, at least and preferably exactly one water-soluble polymer from which the fibers 24 are to be formed is dissolved in a solvent and, for example, in water. The starting solution also contains at least one surfactant. Further, for the at least one polymer of the starting solution A, a plasticizer may be contained in the starting solution A. The polymer may be dissolved in solid form, for example as a powder, in the form of small spheres or pellets or the like in the solvent-serving water of the starting solution A.

[0065] The concentration of the at least one wasserlös ^¬ union polymer in the starting solution A may be 1 wt .-% to 70 wt .-%, preferably 5 wt .-% to 50 wt .-%, more preferably 10 wt .-% to 40 wt .-% amount. If a plasticizer is used for the at least one polymer, be ^¬ meet the specifications of the total concentration of the at least one polymer including the plasticizer.

The concentration of water in the ^{Ausgangslö ¬} solution is in preferred embodiments

30% by weight to 99% by weight, preferably 50% by weight to

95 wt .-% and more preferably 60 wt .-% to 90 wt .-%.

[0067] The concentration of the surfactant in the solution Ausgangslö ^¬ A is the embodiment wt .-% 0.001 to 50 wt .-%, preferably 0.01% to 5 wt .-%, and more preferably 0.1 part by weight before ^¬ % to 1.5% by weight.

The process gas G can be supplied to the process gas connection 13 with a pressure of up to 1000 psi, preferably with a pressure of 5 to 80 psi. When using of air as process gas G, the pressure may be in the range of 10 to 60 psi. The process gas G does during feeding of spinning nozzle assembly 14 is a temperature in the range of 0 ° C to 100 ° C, preferably from 10 ° C to 90 ° C, and more preferably before ^¬ from 20 ° C to 80 ° C. Example According to the Pro ^¬ zessgastemperatur of the process gas G during feeding to the spinning nozzle device 14 is greater than the ambient temperature, for example a room temperature, and may range from 35 ° C to 70 ° C.

The fibers 24 formed by the polymer chains are obtained in the process that on the way between the spinneret 14 and the collector 22, the solvent, here the water, and / or the at least one surfactant completely or at least partially evaporated. That is, the solvent and / or the surfactant to evaporate ^¬ least 85% or at least 90% or at least 95% or at least 99%.

In the method, using the device 10, the fibers 24 are formed. On the collector 22, a nonwoven fabric is formed from the fibers 24, which preferably have a fiber diameter in the micrometer range, in the submicron range or in the nanometer range. The fibers 24 consist essentially of the polymer present in the starting solution A, optionally additionally of the plasticizer used for the at least one polymer.

[0071] The produced fibers 24 preferably have a ratio of length L to an average thickness D of at least 100: 1, preferably at least 500: 1, more preferably at least 1000 before ^¬: 1, and even more preferably at least 10000: 1. Preferably, the fibers 24 a length L of at least one millimeter, preferably at least three millimeters and more preferably at least five millimeters.

Examples 1 to 4 are given below, which describe a possible composition of the starting solution A and features of the device 10.

Example 1 :

To prepare the polymer solution

10 wt .-% polyvinyl alcohol powder (with a molecular weight of 130000 u) dissolved in distilled water (88 wt .-%) and 2 wt .-% of the surfactant polyoxyethylene (23) lauryl ether (known under the trade name Brij-35) was added. From the polymer solution, fine fibers 24 are produced by the solution-blow spinning process. The process is performed using compressed air as the process gas G by ^¬, which is supplied with a pressure of 10 psi to the at least one second outlet nozzle 21st The Wenig ^¬ least a first outlet nozzle 20 has a diameter of 0.6 mm (at the outlet). The distance between the at least one first outlet ^nozzle 20 and the collector ^¬ tor 22 is 65 cm. The hergestell ^¬ th with this method fibers 24 have fiber diameter with a diameter in a range of 50 to 400 nm. The average value of the diameter of the fibers 24 produced is 200 nm.

Example 2:

[0074] The polymer solution is produced from 12 wt .-% polyvinyl alcohol (molecular weight 130000 u), which was dissolved in Destil ^¬ of water required, with the A in the starting solution 87 wt .-% is included. The starting solution A contains

1% by weight of isopropanol. The method is carried out using compressed air as the process gas G, which is supplied at a pressure of 20 psi to the at least one second output ^¬ nozzle 21. The at least one first output ^¬ nozzle 20 has a diameter of 0.6 mm (at the outlet). The distance between the at least one first exit nozzle 20 and the collector 22 is 65 cm. The fibers 24 produced by this method have fiber diameters in a range of 100 to 450 nm. The mean value of the diameter of the fibers 24 produced is 240 nm.

Example 3:

10 wt .-% polyvinyl alcohol (molecular weight 130,000 u) and 2 wt .-% polyvinyl methyl ether are dissolved in 87 wt .-% water. The starting solution A also contains 1% by weight of isopropanol. The process is carried out using compressed air as the process gas G, which is supplied to the at least one second outlet ^nozzle 21 at a pressure of 20 psi. The at least one first exit nozzle 20 has a diameter of 0.8 mm (at the exit opening). The distance between the at least one first exit nozzle 20 and the collector 22 is 65 cm. The fibers 24 produced by this method have fiber diameters in a range of 100 to 500 nm. The mean value of the diameter of the fibers 24 produced is 250 nm.

Example 4:

3 wt .-% polyethylene oxide (molecular weight 600,000 u) are dissolved in 96 wt .-% of distilled water. The starting solution A also contains 2% by weight of isopropanol. The process is carried out using compressed air as the process gas G, the Wenig ^¬ least a second output nozzle 21 is supplied with a pressure of 40 psi to the. The WE ^¬ nigstens a first outlet nozzle has a diameter of 0.6 mm. The distance between the at least one first exit nozzle 20 and the collector 22 is 65 cm. The fibers 24 produced by this method have a fiber diameter in a range of 100 to 500 nanometers. The mean value of the diameter of the fibers 24 produced is 250 nanometers.

The four preceding embodiments or In general, the spinning process according to the invention can be further optimized by the use of additional and / or alternative surfactants. For example, any surfactant and / or polymer can be used which is included in the tables given in the description.

[0078] Further specific examples arise insbeson ^¬ particular by the selection of the composition of the constituents of the starting solution A in the cited in the description areas.

The features of the device 10 given in Examples 1 to 4 can also be used in each case for other compositions of the starting solution A.

[0080] The invention relates to the use of an off ^¬ A temporary solution in the process for producing fibers for a fiber fleece by means of a so-called blow-Solution-spinning. As the solvent for the starting solution A, water is used. In the water of the starting solution A is at least one water-soluble polymer and preferably ge ^¬ exactly dissolved a water-soluble polymer. The starting solution A also contains at least one surfactant and optionally a plasticizer for the at least one respective Po ^¬ lymer used. By means of this starting solution A, it is possible to produce fibers 24 by solution-blow-spinning environmentally friendly. Reference sign list:

10 device

11 storage container

12 pumping device

13 solvent fluid connection

14 Spinneret arrangement

15 process gas connection

16 accumulator

20 first outlet nozzle

21 second outlet nozzle

22 collector

23 liquid jet

24 fiber

25 drive roller

26 suction device

30 outlet nozzle group

A output solution

D thickness of the fiber

G process gas

L length of fiber z nozzle-collector distance

Claims

Claims:

1. Use of a starting solution (A) in a process for the production of fibers and nonwovens (24) by solution-blow spinning, using as solvent for the starting solution (A) What ^¬ ser,

wherein in the starting solution (A) at least one water-soluble polymer is dissolved,

and wherein the starting solution (A) contains at least one surfactant.

2. Use of the starting solution according to claim 1,

characterized in that starting solution (A) as Lö ^¬ solvent exclusively contains water.

3. Use of the starting solution according to claim 1 or 2, characterized in that the starting solution (A) contains exclusively water-soluble polymers.

4. Use of the starting solution according to one of the preceding claims,

is characterized in that at least one wasserlös ^¬ pending polymer is polyvinyl alcohol and / or, polyvinyl methyl ether and / or polyethylene oxide and / or polyvinylpyrrolidone and / or polyethylene glycol and / or polyacrylic acid and / or polyacrylamide.

5. Use of the starting solution according to one of the preceding claims,

characterized in that the concentration of the Sers in the starting solution (A) 30 wt .-% to 99 wt .-% is.

6. Use of the starting solution according to claim 5,

characterized in that the concentration of Was ^¬ sers in the starting solution (A) is 50 wt .-% to 95 wt .-%.

7. Use of the starting solution according to claim 6,

characterized in that the concentration of What ^¬ sers in the starting solution (A) is 60 wt .-% to 90 wt .-%.

8. Use of the starting solution according to one of the preceding claims,

characterized in that the concentration of min ^¬ least one water-soluble polymer in the starting solution (A) 1 wt .-% to 70 wt .-% by weight.

9. Use of the starting solution according to claim 8,

characterized in that the concentration of min ^¬ least one water-soluble polymer in the starting solution (A) 5 wt .-% to 50 wt .-% by weight.

10. Use of the starting solution according to claim 8,

characterized in that the concentration of min ^¬ least one water-soluble polymer in the starting solution (A) 10 wt .-% to 40 wt .-% by weight.

11. Use of the starting solution according to one of the preceding claims,

characterized in that the concentration of min. at least one surfactant in the starting solution (A) is 0.001% by weight to 50% by weight.

12. Use of the starting solution according to claim 11,

characterized in that the concentration of min ^¬ least one surfactant in the starting solution (A) 0.01 wt .-% to 5 wt .-% by weight.

13. Use of the starting solution according to claim 12,

characterized in that the concentration of min ^¬ least one surfactant in the starting solution (A) 0.1 wt .-% to 1.5 wt .-% by weight.

14. Use of the starting solution according to one of the preceding claims,

characterized in that the at least one surfactant has the property of at least partially evaporating during solution-blow spinning.

15. Use of the starting solution according to one of the preceding claims,

characterized in that the starting solution (A) contains solid particles.

16. A process for producing fibers (24) by solution-blow spinning, using a ^{Ausgangslö ¬} solution (A) according to any one of the preceding claims, comprising the following steps:

Outflow of the starting solution (A) from at least one first outlet nozzle (20),

- Outflow of a process gas (G) from at least ei ^¬ ner second exit nozzle (21), which adjacent to the at least one first exit nozzle (20) arranged is, simultaneously with the outflow of the starting solution (A).

17. The method according to claim 16,

characterized in that the method for the manufacture of microfibers ^¬ lung and / or Submikrofasern and / or nanofibers and nonwoven fabrics formed from it is used.

18. The method according to claim 16 or 17,

characterized in that the process gas (G) is supplied to the at least one second exit nozzle (21) under a pressure of 0.1 to 100 psi.

19. The method according to claim 18,

characterized in that the process gas (G) is supplied to the at least one second exit nozzle (21) at a pressure of 5 to 80 psi.

20. The method according to claim 19,

characterized in that the process gas (G) is supplied to the at least one second exit nozzle (21) under a pressure of 10 to 60 psi.

21. The method according to any one of claims 16 to 20,

characterized in that the process gas (G) with ei ^¬ ner temperature of 0 ° C to 100 ° C to the at least ei ^¬ nen second outlet ^nozzle (21) is supplied.

22. The method according to claim 21,

characterized in that the process gas (G) with ei ^¬ ner temperature of 10 ° C to 90 ° C to the at least ei ^¬ nen second outlet ^nozzle (21) is supplied.

23. The method according to claim 21,

characterized in that the process gas (G) with ei ^¬ ner temperature of 20 ° C to 80 ° C to the at least ei ^¬ nen second outlet ^nozzle (21) is supplied.

24. The method according to any one of claims 16 to 23,

characterized in that the solvent in the starting solution (A) after exiting the at least one first exit nozzle (20) at least partially or predominantly evaporated.

25. Nonwoven fabric produced by a method according to one of claims 16 to 24.